CSR--EHS: Virtual Execution Environments for Heterogeneous Embedded Devices

嵌入式设备的日益普及（占当今制造的所有CPU的99%以上）推动了对高级执行环境的需求，以解决嵌入式系统的许多重要问题。动态重编程、故障隔离和恢复、处理有限的硬件资源以及自动适应只是其中的几个激励问题。当前，许多通用计算机除了操作系统之外还使用虚拟执行环境（VEE）来提供元执行功能，包括软件和硬件兼容性、动态优化、剖析和安全性。当应用程序在目标体系结构上执行时，VEE透明地、自动地对应用程序进行中介、控制和调整。尽管有这些好处，但由于这些设备的内存和功耗限制，VEE的功能尚未在嵌入式设备中实现。此外，嵌入式设备的资源配置文件导致需要探索和开发新的策略。本项目探讨了专门为嵌入式设备的资源配置文件设计的新虚拟化技术。该研究正在VEE技术中取得一些根本性的进展，包括减少内存占用，设计在众多嵌入式平台上运行的VEE，以及有效地卸载无法在资源受限的节点上执行的大型计算。最终目标不是专注于特定设备的单个VEE，而是探索整个VEE设计空间连续体，评估各种嵌入式设备的众多设计选项和权衡。作为第一步，这个项目探讨了三个常用的嵌入式设备：PDA，手机和传感器节点的新设计点。

The increasing prevalence of embedded devices, which account for over 99% of all CPUs manufactured today, drives the need for an advanced execution environment that addresses a number of important problems for embedded systems. Dynamic reprogramming, fault isolation and recovery, dealing with limited hardware resources, and automatic adaptation are but a few of the motivating issues. Currently, many general-purpose computers use a virtual execution environment (VEE) in addition to the operating system to provide meta-execution functionality, including software and hardware compatibility, dynamic optimization, profiling, and security. The VEE transparently and automatically mediates, controls, and adapts an application as it executes on the target architecture. Despite the benefits, the power of VEEs has yet to be realized for embedded devices due to the memory and power constraints of these devices. Furthermore, the resource profiles of embedded devices lead to the need for new strategies to be explored and developed.This project explores new virtualization technology specifically designed for the resource profiles of embedded devices. The research is making several fundamental advances in VEE technology including reducing the memory footprint, designing VEEs that function on the multitude of embedded platforms, and efficiently offloading large computation that cannot be performed on resource-constrained nodes. Rather than focusing on a single VEE for a particular device, the ultimate goal is to explore the entire VEE design space continuum, evaluating the numerous design options and trade-offs for a variety of embedded devices. As a first step, this project explores new design points for three commonly used embedded devices: the PDA, the cell phone, and the sensor node.